Relayed communication with versatile self-interference cancellation

Methods, apparatuses, and systems are presented for providing self-interference cancellation in two-way relayed electromagnetic communication between a first and a second device through a relay station, involving retrofitting existing equipment comprising a transmitter system and a receiver system at the first device by adding a canceler module, providing a version of a modulated near signal as a first non-baseband interface signal from the transmitter system to the canceler module, providing a version of a composite signal as a second non-baseband interface signal from the receiver system to the canceler module, generating a cancellation signal at the canceler module corresponding to a relayed version of the modulated near signal, using the first and the second non-baseband interface signals, applying the cancellation signal at the canceler module to a version of the second non-baseband interface signal, to produce a cancellation-processed signal as a third non-baseband interface signal provided to the receiver system.